A person does not need to have undergone any medical treatment to be trans; the term you are looking for is pre-op or non-op. Non-binary people for instance often don't go through any surgical procedures, a lot of trans women don't opt for bottom surgery (Vaginoplasty), and a lot of trans men bind their breasts instead of opting to have them removed. Some do, some don't - it's an individual preference that has no bearing on whether or not you are trans.

Also, being trans isn't a sexuality. There are gay trans people, there are straight trans people, and there are ace transpeople. A transwoman who is pre-op "wouldn't just be a homo", she's a valid trans woman who would be in a straight relationship if she is with a man, or a gay one if she's with a woman. It's generally pretty accepted that you've been this way from birth - although it can take decades to realize that.